Steam-pressure gage



2 Sheets SheEet 1. T. W. LANE.

Stam Pressure Gage. No. 23,032. 5 Patented Feb. 22, 1859.

N. PETERS. PhDIo-Lfinagrzphen Washi c.

2 Sheets-Sheet 2.

T. W. LANE.

Steam Pressure Gage.

Patented Feb. 22,

tenor of the gage.

mm s'rnrns PATENT orricn THOMAS W. LANE, OF MEREDITH, NEW HAMPSHIRE.

srnAivr-rnnssnnn GAGE.

Specification formingpart of Letters Patent No. 23,032, dated February 22, 1859; Reissued March 11, 1873', No. 5,320.

To all whom it may concern:

Be it known that I, THOMAS WILSON LANE, of Meredith, in the county of Belknap and State of New Hampshire, have invented certain new and useful Improvements in Steam- Pressure Gages, of which the-following 1s a full, clear, and exact description, reference being had to the accompanying drawlngs, making part of this specification, in which- Figure 1 is a view of my lmproved gage the dial plate being removed to show the 1n- Fig. 2 a similar view of the Bourdon steam gage as heretofore constructed; Fig. 3 the dial plate. Figs. l, 5 and 6will be referred to hereafter.

Steam gages in which the pressure of steam within a'boiler is measured by the alteration of form of a flattened tube, are preferable on many accounts to any other form ofgage thus far constructed or introduced. They are sensitive to light pressures and are not liable when properly made to be ruptured or set by the heaviest pressures which they are called upon to endure. They are however liable to some objections, which are due not to their principle of action, but to faults in the construction and arrangement of their parts.

In Fig. 2 of the accompanying drawings is represented a gage of this description of the usual construction, the bent tube A, being attached at one extremity to the pipe B, through which the pressure within the boiler is transmitted to the interior of the tube. lVhen thus constructed if the bent tube exceed a semicircle in length, a portion of the tube (as from c, to f, Fig. 2) hangs down below the point 6, so as to form a receptacle in which water soon accumulates from the condensation of vapor within it. The water thus collected is liable to freeze in winter by which the indicating tube is often burst or strained. To remedy this difficulty it is necessary so to combine the bent tube with the pipe that any water that may condense within the tube shall drain back into the pipe, but it is manifest that a tube attached to its pipe as represented in Fig. 2, will not thus drain itself in any position in which it can be placed. V

To accomplish this end is the object of the first part of my invention which consists in so combining the indicating tube withthe pipe through which the pressure within the boiler is transmitted to the gage, that the length of tube in any direction from its junction with the pipe, shall not exceed a semlcirole, and in placing the tube in such a posltion that it shall descend at every point toward its into the pipe.

WVhen used upon locomotives the gage represented in Fig. 2, is liable to another serlous objection, arising from the violent shocks and jarring to which the engine is subjected as it passes over the road. These shocks are of a two fold character1st those which are occasioned by obstacles encountered by the treads of the wheels (as the ends of rails, &c.) and which occur in directions nearly vertical; 2nd those which are occasioned by the swaying of the engine from slde to side, and by the striking of the flanges or fillets of the wheels against the sides of the rails and which occur in horizontal directions. The first class of these disturbances communicate to the bent tube ably augmented by the water of condensation which is allowed to. collect and remain within the tube and which materially increases its weight and momentum.

To diminish as far as possible the vertical vibrations of the tube as well as to do away with their influence upon the index hand is the object of the 2nd part of my invention which consists in joining the pipe through which the pressure within the boiler is transmitted to the gage, with the indicating tube, at a point between the two ends of the tube and bending the latter upon opposite sides of a vertical linepassing'through its junction with the pipe, whereby the tube is rendered less sensitive to the effects of the vertical shocks to which the locomotive is subjected. The length of tube which I have junction with, and drain back:

found to be least affected by these shocks is nearly a complete circle, to the center of which the pipe from the boiler is joined, the two ends of the tube approaching each other at the top where they are connected with the lever which transmits their motion to the index hand. But this arrangement may be slightly departed from without materially varying the resultfor instance the extreme ends of the tube may be carried farther from each other than is above indicated, or they may be brought nearer together and even be allowed slightly to pass each other, without greatly modifying the result. As before stated however I have found the form and position of the bent tube first above indicated and shown in Fig. 1, as best calculated to diminish the efiects of the vertical jars upon the indicating tube and index hand. By the above construction the horizontal vibrations of the tube are also materially lessened.

To prevent the transmission of these horizontal vibrations and to diminish as far as practicable their influence upon the index hand is the object of the 3rd part of my invention which consists in bending the two portions of the indicating tube symmetrically or nearly so upon opposite sides of the vertical line passing through the junction of the tube with the pipe from the boiler, and connecting the two extremities of the tube with the lever which transmits their motion to the index hand in such a manner that the sidewise motion or vibration of one extremity of the tube shall counteract the side motion of the other extremity, and prevent the horizontal vibration of the tube from being transmitted to or otherwise influencing the motion or position of the index hand.

In Fig. 6 the lever i is pivoted to the case at 3, and is connected with the two branches of tube at 4, and 5. It is obvious that with a lever thus pivoted a single branch of the tube will produce as great a motion of the lever and index hand as the two branches combined, and in order that suflicient motion may be transmitted to the index hand it is necessary that the distance of the points of attachment 4', and 5, from the pivot 8, be quite short. But the shorter this dis tance is, the greater will be the effect upon the index hand of any ar of the indicating tube, and also the greater will be the dis turbing effect upon the hand produced by any wear of the pivots 3, 4, and 5. On this account it is desirable that the distance between the points of attachment of the tube with the transmitting lever, and the pivot upon which this lever turns be as great as is practicableand still afiord the necessary range of motion to the index hand.

To accomplish this and thus still further to diminish the effect upon the index hand of any vibrations to which the indicating tube may be exposed as well as to render the motion of the two branches of the indicating tube available is the object of the 4th part of my invention which consists in hanging or pivoting the lever which transmits the motion of the indicating tube to the index hand, to one of the branches of the tube, without pivot to the case or other rigid part connected therewith and connecting the other end of the tube with the lever in such a manner that the points of attachment to the lever shall form the fulcra around. which the lever turns.

To enable others skilled in the art to understand my invention I will proceed to describe the manner in which I have carried it out.

In Fig. 1, of the accompanying drawings is represented my improved gage, the dial plate (seen detached in Fig. 3) being removed to show the parts within.

The pipe C through which the pressure is brought from the boiler is attached to the the two branches 1, and 2, of the indicating tube are made of a length not exceeding a semicircle while they are both so placed as to descend at every point toward their junction with the pipe 0 that the water which may condense within the tube may drain back to the pipe. It is obvious that so far as mere drainage is concerned the indicating tube in lieu of consisting of two branches as in Fig. 1 may be much shorter even less than a semicircle as represented at C in Fig. 4, or of two branches arranged as in Fig. 5, on account of other which will be explained in treating of the other branches of my invention, the construction shown in Fig. 1 is to be preferred.

To diminish as far as possible the vertical vibrations of the indicating tube and to lessen their influence upon the index hand which is the object of the second part of my invention the pipe C, is joined with the .tube at a point T, between its two extremities and the two branches 1, and 2, are bent upon opposite sides of the vertical line 00, 50, passing through the point T, the extremities of the tube being nearly over the points 3 y, where the tubes is rigidly supported.

It is manifest that'so far as the vertical jars are concerned, the tube represented in Fig. 4, and consisting of a single branch C if properly connected with an index hand would answer the purpose but although it might serve to carry out both the 1st and 2nd parts of my invention it would obviously still be exposed to the objections arising from the horizontal vibrations, to remedy these the tube is formed of two branches 1 and 2, which are bent symmetrically upon opposite sides of the vertical line considerations however m, m, that their motions in a horizontal direction may coincide as nearly as possible -mitted to the index hand is pivoted to one of the branches (1,) of the tube at s, the extremity of this lever being pivoted at r, to a connecting arm 9 the other end of which is pivoted at 0, to the branch (2) of the tube. The lower end of the lever i is pivoted at 1), to the rack m, which engages with a pinion n, upon the arbor of the index hand P. l/Vhen thus constructed and connected it will be observed that upon the occurrence of a shock in a horizontal direction, both branches of the tube move equally or very nearly so in the same direction, carrying with them the upper end of the lever 2' which not being pivoted to the case or other rigid part of the gage simply turns around the point 11, without influencing the rack m or the index hand.

Where the lever 2' is pivoted to the case as in Fig. 6 the forces with which the two branches of thetube are thrown in one di- 7 rection by a horizontal shock are brought to bear upon the pivot 3, in opposite directions by which they, mutually counteract each other and no effect is produced upon the index hand.

In the gage represented in Fig. 6, the first, second and third parts of my invention are carried out but this construction is liable to the objections which it is the object of the fourth part of my invention to remove1st it will be difiicult to adjust the points of attachment 4 and 5, so as not to cause the pivot 3 to bind in its bearings; 2nd the jarring of the indicating tube whether in a vertical or horizontal direction brings great strain and wear upon the pivot 3 whereby it or its bearings are soon worn; 3rd the effect upon the index hand of the looseness of parts thus produced as well as of the jarring of the tube, is greatly increased by the shortness of the distance between the pivot 3 and the points 4, and 5. I do not therefore propose to adopt thisconstruction but to employ that represented in Fig. 1 in which the lever i is hung upon one of the branches of the indicating tube as before described in lieu of being rigidly pivoted to the case. By means of this construction I am enabled to avail myself of the aggregate motion of the branches 1 and 2, of the tube while the short arm of the lever 2' may be made of double the length which it would be necessary to have if this lever were pivoted to the case, the point- 7' serving as fulcrum for the motion imparted to the lever by the branch 1 of the tube and the point .9 as fulcrum for the motion imparted to it by the branch 2. The aggregate motion of the two branches of the tube is thus made available and I am therefore enabled as before stated to double the length of the short arm of this lever and thereby greatly diminish the vibration of the index hand when the indicating tube is subjected to ars.

The extremity of the lever 2' to which is pivoted the connecting arm 9 (Fig. 1) is made in a separate piece 2?, which is fitted to slide into the body of the lever t' and is secured in the required position by the screw 0, by which means the distance between the pivots r and 8, may be varied.

A delicate coiled spring a, one end of which is attached to the bottom plate 2, and the other to the pinion n, serves to keep the teeth of the latter pressed against one side of the teeth of the rack m. The rack m, is prevented from being raised by any sudden jar and disengaged from the teeth of the pinion n, by a shoulder on the top plate d seen dotted at Z), Fig. 1.

l/Vhat I claim as my invention and desire to secure by Letters Patent is- 1. So combining the indicating tube with the pipe through which the pressure within the boiler is transmitted to the gage that the length of tubein either direction from its junction with the pipe, shall not exceed a semicircle, and placing the tube in such a position that it shall descend at every point toward its junction with and drain back into, the pipe.

2. I claim joining the pipe from the boiler with the indicating tube at a point between its two ends, and bending the latter as set forth so that the ends of the tube shall be nearly over the points where its two branches are rigidly supported, whereby the tube is rendered less sensitive to the vertical shocks to which it is subjected.

3. I claim bending the two portions of the indicating tube symmetrically or nearly so upon opposite sides of a vertical line, as described and connecting the two extremities of the tube with the lever i as set forth for the purpose of preventing the horizontal vibrations of the tube from being transmitted to the index hand.

for the purpose specified. '1

T. w. LANEJi Witnesses:

THos. S. RoAoH, SAM. COOPER.

[FIRST PRINTED 1910.] 

